The invention relates to zero insertion force (ZIF) sockets.
Zero insertion force sockets are commonly used to attach integrated-circuit (IC) modules to printed circuit (PC) boards. As shown in FIG. 1, a known ZIF socket includes a top plate 100 that is slideably attached to a base 102. Top plate 100 contains apertures 104 and the base 102 contains a corresponding number of openings 106. The openings 106 house spring elements 108, each of which has a tail portion 110 that is soldered to the PC board. The ZIF socket further includes a camshaft 114 located inside a raised portion 116 of top plate 100. Rotating a lever 118 causes camshaft 114 to act on base 102, displacing top plate 100 with respect to base 102, which is anchored to the PC board via the tail portions 110.
The terminals or pins of an IC module, such as a microprocessor, are inserted into an open ZIF socket, and protrude through apertures 104 of top plate 100. With the socket in its open position, apertures 104 and corresponding spring elements 108 are not aligned, so that no contact exists between the pins of the IC module and spring elements 108. The lever 118 is then rotated downwards, the camshaft 114 exerts a force on base 102 which causes top plate 100 to translate relative to base 102, such that the pins of the IC module and spring elements 108 align and engage.
New, faster, lower voltage microprocessor bus circuits are more susceptible to failure or performance degradation due to noise on many signal lines. Conventional ZIF sockets for use with such circuits do not prevent crosstalk or other noise which could occur between adjacent pins.
A shielded socket for use in a zero-insertion-force (ZIF) socket assembly is presented. The socket includes a conducting plate including a plurality of apertures, and an insulating layer. The insulating layer surrounds the conducting plate and lines at least one signal carrying passageway. In an implementation, the conducting plate includes at least one grounding site. A slider plate assembly may be included that slideably connects to an outside wall of the insulating layer to form the ZIF socket assembly.
A ZIF socket assembly according to the invention is compatible with high front or back-side bus speeds (i.e. speeds currently being developed for future central processing unit (CPU) components) because it reduces cross-talk between the pins of the CPU. In addition, the shielded ZIF socket has a low profile configuration, which minimizes the potential for signal degradation and timing problems due to excessive trace length. Thus, such a shielded, low-profile ZIF socket finds applications in high-bus-speed CPU socketing, especially for thin notebook computers.
Other advantages and features of the invention will become apparent from the following description and the claims.